The present invention relates to a horizontal converter adapted for use in the synthesis of ammonia. More particularly, the present invention involves a converter which has at least two horizontal catalyst beds with a low pressure drop design and where all the synthesis gas passes through each of the catalyst beds. Unique to the converter is an inner cylindrical shell or basket with a gas transfer section which passes the preheated synthesis gas to the top of the first catalyst bed and passes the gas from the bottom of the first catalyst bed to heat exchange tubes before passing through a tube to the second catalyst bed.
The conventional ammonia converter is a vertical converter. A vertical "quench type" reactor is illustrated in U.S. Pat. No. 3,475,136. A "quench type" converter is one wherein cold reactant gas is mixed with the hot reactant gases flowing from one catalyst bed before passing through another catalyst bed to regulate the temperature of the gases. In U.S. Pat. No. 3,567,404, a horizontal quench type converter is disclosed which uses a series of concentric pipes to inject quench gas. In U.S. Pat. No. 4,180,543, an ammonia converter is disclosed with parallel catalyst beds to lower the pressure drop.